The Environmental Health Sciences Center for which this proposal seeks continued support, has as a goal the study of the toxicology of environmental chemicals. Its objectives in pursuit of this goal are: 1. To identify and investigate critical environmental health problems, provide analyses and suggest methods of solving. 2. To conduct in-depth research on health aspects of environmental chemicals in such areas as: Chemodynamics, mathematical modeling, metabolism and mechanism of action and effects from molecular to whole organism level. 3. To attempt to develop new approaches in the investigation of the toxicology of environmental chemicals. Through a coordinated interdisciplinary program, research on such problems as the dynamics (distribution and fate) of chemicals in the environment and animals, the biological effect of such chemicals at the molecular, tissue and organ to whole organism level and the mechanism by which these effects are produced. To provide the sophisticated equipment and approaches required in such investigation, special core laboratories - e.g. analytical chemistry biometry, pathology will be supported by the center.